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以对称式微位移缩小机构和柔性铰链相结合,压电陶瓷驱动的微进给刀架可实现精密加工,但刀架的迟滞特性影响其定位精度。该文根据非线性Preisach模型的理论知识及压电陶瓷驱动微进给刀架的电压位移特性,将模型进行修改后得到刀架迟滞特性的数学模型,并对数学模型式进行离散化处理。实验结果表明,改进后的迟滞模型形式简单,数据采集简便,模型描述精确,能较好地实现压电驱动微进给刀架的迟滞建模,提高了迟滞模型的实用性。为提高压电陶瓷驱动微进给刀架的定位精度,实现精密控制打下基础。 相似文献
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传统preisach模型具有次环一致特性,压电陶瓷执行器迟滞特性不满足其特性。采用传统preisach模型建模精度较低,因此,该文提出一种改进型preisach模型,推导出离散化计算方法,其数值实现采用三线性插值法。在PI公司生产的E 625系列压电陶瓷控制器平台上针对此算法进行相关实验设计和结果的验证。实验结果表明,该文提出的基于三线性插值法的preisach模型其绝对误差最大值为0.2 μm,提高了压电陶瓷preisach模型精度。 相似文献
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压电驱动器迟滞特性的Preisach模型研究 总被引:15,自引:2,他引:13
压电驱动器的迟滞特性是影响其位移输出精度的主要因素。该文采用改进的Preisach模型对压电驱动器的迟滞特性进行建模,并进行了相应的实验研究。实验结果表明该模型可以很好地预测压电驱动器在经过一定的控制电压序列以后的位移输出值.能够有效地降低迟滞特性对压电驱动器位移输出精度的影响。 相似文献
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压电陶瓷微位移特性的电脑接触式干涉测量法 总被引:5,自引:1,他引:4
介绍了压电陶瓷微位移器的工作原理,在此基础上提出了一种用由立式接触式干涉仪改造的电脑接触式干涉仪测量微位移特性的方法。其完善的测试软件系统,实现了对压电陶瓷微位移量的自动化、智能化精密测量。并对自行设计的压电陶瓷微位移装置进行了测试,得出电压-位移的关系曲线和迟滞曲线,精度和重复性值达0.01μm。 相似文献
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针对压电陶瓷执行器的迟滞非线性特性问题,该文提出了一种最小二乘法与径向神经网络相结合的建模方法。首先,通过搭建压电执行器位移测试系统,得到执行器输出位移与输入电压的对应曲线关系,然后用最小二乘法对该曲线进行多项式拟合,得到压电执行器的迟滞数学模型,在此基础上再用径向基函数神经网络方法对该模型进行优化。最后对建立的模型进行分析发现,用最小二乘法拟合的多项式数学模型,其最大误差Emax=0.244 7 μm,标准方差δ=0.059 02 μm,而利用径向基函数(RBF)神经网络优化建模后,Emax=0.079 89 μm,δ=0.016 04 μm。实验证明该模型有较高的准确性, 该文为压电执行器迟滞建模提供了一种新的方法。 相似文献
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《Mechatronics》2006,16(2):97-104
The LuGre model which has been widely used to describe the friction phenomenon for mechanical systems consists of stiffness and viscous terms. The stiffness term of the LuGre model shows the friction torque to act linearly for the internal state of friction dynamics. Thus it cannot represent the hysteresis phenomenon of friction in the pre-sliding phase. Especially the hysteresis has the non-local memory characteristics. In this paper, the non-local memory hysteresis phenomenon is analyzed through experiments and the improved friction model using the Preisach model is proposed. In order to implement the Preisach model, the neural network algorithm is used to increase the efficiency of the Preisach algorithm. Based on the improved friction model, the adaptive back-stepping sliding mode controller (SMC) is designed to improve tracking performance in the sliding and pre-sliding phases. To evaluate the performance of the proposed friction control system, experiments are executed for a ball-screw servo system and the satisfactory results are shown. 相似文献
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Tracking control of a piezoceramic actuator with hysteresis compensation using inverse Preisach model 总被引:6,自引:0,他引:6
G. Song Jinqiang Zhao Xiaoqin Zhou J.A. De Abreu-Garcia 《Mechatronics, IEEE/ASME Transactions on》2005,10(2):198-209
This paper presents the classical Preisach hysteresis modeling and tracking control of a curved pre-stressed piezoceramic patch actuator system with severe hysteresis. The actuator is also flexible with very small inherent damping. It has potential applications in active antennas. A series of tests are conducted to study the hysteresis properties of the piezoceramic actuator system. The numerical expressions of the classical Preisach model for different input variations are presented. The classical Preisach model is applied to simulate the static hysteresis behavior of the system. Higher order hysteresis reversal curves predicted by the classical Preisach model are verified experimentally. The good agreement found between the measured and predicted curves showed that the classical Preisach model is an effective mean for modeling the hysteresis of the piezoceramic actuator system. Subsequently, the inverse classical Preisach model is established and applied to cancel the hysteresis the piezoceramic actuator system for the real-time microposition tracking control. In order to improve the control accuracy and to increase damping of the actuator system, a cascaded PD/lead-lag feedback controller is designed with consideration of the dynamics of the actuator. In the experiments, two cases are considered, control with major loop hysteresis compensation, and control with minor loop hysteresis compensation. Experimental results show that RMS tracking errors are reduced by 50% to 70% if the hysteresis compensation is added in the feedforward path in both cases. Therefore, hysteresis compensation with the feedback controller greatly improves the tracking control accuracy of the piezoceramic actuator. 相似文献
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The hysteretic behavior of a plant with a non-negative input, referred to as one-sided hysteresis, is characterized by an initial ascending curve and hysteresis loops. It is observed that the widely-used classical Preisach hysteresis model and its modifications cannot represent such one-sided hysteresis due to the limitation of the Preisach hysteresis operator. To address this issue, a novel hysteresis operator modified from the Preisach hysteresis operator is proposed in this study and on this basis, a rate-independent hysteresis model and a rate-dependent hysteresis model are developed with methods to estimate their parameters. An algorithm to invert the rate-independent hysteresis model and its application to tracking control are also presented. The models and control schemes developed were verified experimentally on a commercially-available piezoelectric actuator. The results obtained show that the models developed are promising to represent the one-sided hysteresis of the piezoelectric actuator and that the inverting algorithm of the rate-independent hysteresis model is effective as applied to the tracking control of piezoelectric actuators. 相似文献
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In this paper, the classical Preisach independent domain model is used to capture the essential characteristics of hysteresis nonlinearity in electromagnetic (EM) actuators made of soft ferromagnetic material. Experimental results demonstrate its ability to accurately model electromagnetic hysteresis for variations in input current, airgap, and orientation. The Preisach model is then inverted and incorporated in an open-loop control strategy that regulates the EM actuator and compensates for hysteretic effects; hysteresis-free regulation of the EM actuator is obtained, for variations in input current, airgap, and orientation. Hysteresis is also effectively compensated for desired force trajectories of frequencies up to 100 Hz. Thus, the experimental results demonstrate consistent performance of the open-loop control strategy based on Preisach model inversion, in satisfactorily regulating the output of the EM actuator to the desired trajectories 相似文献
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Sjostrom M. Djukic D. Dutoit B. 《Applied Superconductivity, IEEE Transactions on》2000,10(2):1585-1592
High-temperature superconductors (HTS) exhibit hysteresis, which is the main cause for losses in the subcritical domain. This behavior is well predicted by Bean's critical-state model, which is a subset of the classical Preisach model. We present a parameterized Preisach model that describes the hysteresis of HTS specimens in self-field, where the parameters are identified from electrical lock-in (loss) measurements. That means the model can be used independent of geometry, number of filaments, and other physical measures as long as Bean's model applies. An advantage of the model is that it can predict outputs (flux, voltage) and losses for arbitrary input currents once the HTS has been characterized from measurements. We have further derived exact models for the hysteretic losses in strip and elliptic geometry strips, where the energy losses were calculated by Norris 相似文献
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《Mechatronics》2003,13(2):85-94
A classical Preisach model [Mathematical Models of Hysteresis, Springer, New York, 1991] is developed using a piezoceramic actuator in a stacked form. The classical Preisach model is shown to offer excellent modeling accuracy when the actuator is not subject to any load and is subject to an excitation voltage signal at a low frequency. The accuracy of the Preisach model is shown to increasingly deteriorate as the load being applied to the piezoceramic actuator is increased or the range of frequencies contained in the voltage excitation signal gets wider. The classical Preisach model remains, though, a good model for hysteresis in piezoceramic actuators in applications where the load fluctuation is relatively small and the range of frequencies of the voltage excitation is limited. 相似文献
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该文对压电驱动器建模与控制技术进行了研究。通过二阶系统描述了压电驱动器的线性动态特性。基于Preisach迟滞模型,提出了全新的简化模型,避免了Preisach模型中复杂的双重积分运算。通过前馈与反馈控制技术相结合,为压电驱动器设计了一个综合控制器。在前馈控制器中,通过Preisach模型描述逆迟滞环,有效解决了Preisach模型不可逆的问题。通过比例、积分、微分(PID)反馈控制器,有效提高了系统鲁棒性,并有效补偿了前馈控制器中模型不精确带来的误差。最终,通过实验分别验证了模型的有效性及控制器的控制作用。 相似文献
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《Mechatronics》1999,9(4):391-410
To facilitate on-line identification and implementation of a piezoelectric actuator model for precision machining, this paper describes a hybrid hysteresis model integrating the classical Preisach model and a neural network. The incorporation of a neural network enables on-line model identification from operating data of a piezo (a great contrast to the tedious calibration process required by the classical Preisach model). The model is then extended to describe a piezo actuator’s frequency dependent behavior which is not possible for the classical model. Experimental results confirmed the accuracy of both models and the superiority of the extended one. 相似文献